1. The Field of the Invention
This invention relates to an improved catheter affixation and anchoring device. More particularly, this invention relates to a novel apparatus for positioning a catheter in a desired configuration and anchoring the catheter assembly to the body of a patient.
2. The Background Art
Heretofore, means for securing catheter assemblies and cannula securing devices have varied widely. Some have been either simplistic in function and effectiveness or excessively invasive. Others have been comprised of multiple components and adapted for use in only a limited number of applications for administration of parenteral fluids. Typically, these latter methods and devices have been time consuming to use, have required multiple components for assembly and varied materials for manufacture of such multiple components, have included relatively complicated structural features, and have been adaptable for use in only a limited number of specific medical procedures.
In common nonproprietary practice, a catheter is affixed to a medical patient by use of an adhesive or surgical tape placed over the catheter atop the skin. Similarly, the hub between the catheter and cannula is also maintained in place by tape. A safety loop is typically formed in the catheter tubing to ensure that any tension applied to the catheter is not passed directly to the cannula, but instead is taken up in the slack of the safety loop. As expected, each of the several times this taping process is to be performed over the course of a given catheterization procedure, a considerable amount of the time of a medical practitioner is consumed. Moreover, this somewhat complicated taping process must be repeated several times in this outmoded approach, such that substantial tape is wasted. Furthermore, the frequent application and removal of typically strong adhesive tape regularly results in the excoriation of the skin underneath the tape and at the site of the cannula insertion. Difficulties attendant to removal and reapplication of tape in this context give practitioners incentives to change the tape less frequently, thereby causing increased incidence and severity of infection and skin suffocation. The ability of practitioners to view the site covered by tape is also diminished in indirect proportion to adequacy of the amount of tape used.
Occasionally the attachment of the catheter is effected or enhanced by an actual suturing of the catheter to the skin of the patient. The difficulties of cleaning, pain, potential scarring, and increased risk of infection inherent in this approach are all readily apparent. In addition, many states currently require a license before this type of suturing procedure can be used.
Several relatively cumbersome proprietary devices have recently proliferated. One system, the Intravenous Vascular Stabilizer of U.S. Pat. No. 4,316,461 issued to Marais et al. on Feb. 23, 1982, describes a device with at least four parts, with the commensurate rise in manufacturing complexity and cost. Two of the parts, which are made of a more pliant material than the other semi-rigid parts, perform the function of anchoring the device with straps around a limb of the patient. A number of clips can be attached to the device to accommodate infusion tubing, Y connectors and the like. The functional application of this device is limited to vascular infusion, as well as elevation and lateral stabilization of the blood vessels which are to be infused.
Another device whose function is limited to circumstances involving intravenous infusion, the Intravenous Anchor and Wound Shield of U.S. Pat. No. 4,449,975 issued to Perry on May 22, 1984, likewise utilizes straps for fastening the device to a limb of the patient. Devices conforming to this disclosure require at least three parts, two of which form the two straps which anchor the semi-rigid device in place. The catheter leads from the cannula and hub through the straps and over the semi-rigid portion of the device. Then the catheter is characteristically bent to double back in a safety loop and interweave through the straps in the opposite direction. While one object of this device is to provide an anchoring system in which the amount of adhesive contact with the skin is substantially reduced, the strapping implements on this apparatus and devices of a similar design may tend to constrict the circulatory flow within the limb to which the apparatus is anchored. Another disadvantage is the potential for lateral migration of the catheter underneath the anchoring straps. Such a migratory shift in the positioning of one length of the catheter can result in patient discomfort as the fastening straps press the catheter into the skin of the patient or, worse, cause a segment of the catheter tube near the apex of the catheter safety loop to collapse and thereby partially or completely restrict the steady flow of parenteral fluids to the body.
The Catheterization System described in U.S. Pat. No. 4,711,636 issued to Bierman on Dec. 8, 1987, is likewise comprised of multiple parts of varied materials with narrow application, addresses the potential for lateral migration by essentially affixing the cannula, needle or other stylet to the device itself. The catheter is replaceably connected to a channel through the device which is in fluid communication with the cannula. The cannula remains in-dwelling within the body of the medical patient. Accordingly the device is intended to be self-adhered to the skin one time only throughout the duration of the catheterization procedure, allowing changing of the catheter tubing only. This approach by design inherently possesses the potential for accumulation of microbial contamination at and near the insertion site. In addition, the device necessarily must utilize a specially designed, customized tubing, preventing its applicability to more universally available and less expensive catheter resources.